The present invention relates to a combined payload container and fastening structure for such a container to be used in combination with space vehicles for purposes of transporting and operation of any content in that container.
Presently payloads, e.g. experimental devices or communication arrangements and devices or the like, are provided in a space vehicle as a fixed installation. They fulfill their task either until the experiment had been completed or until it has to be stopped or is stopped for reasons of a tecnhical breakdown, or at the end of the use life of the space vehicle as a whole. If the vehicle is to have a longer use-life, that is for example if it is going to be re-used, it has to be removed from orbit and brought back to Earth which of course is very expensive, and following any repair and/or refurbishing or the like, the vehicle is then placed back into orbit. It is often simpler and more economical to just abandon any defective space vehicles part or payloads and provide new ones instead in orbit.
Exchanging payloads presupposes a certain kind of standardized system in terms of structure generally but also regarding relevant mechanical and/or electrical communication and thermo-technical engineering aspects as well as features related thereto and involving particularly the connection between payloads on one hand and the space vehicle structure on the other hand including power supply waste disposal or just return paths or the like.
U.S. patent application, Ser. No. 028,238, filed Mar. 20, 1987 in the U.S. Patent Office (see also German patent application No. P 36 09 770.5), discloses a payload transport and operating device for space vehicles which has at its principal goal the extension of the use-life of on-board equipment. In that particular application payload containers are described which can be assembled from various standardized basic elements so as to accommodate different sizes for different experiments, loads or the like. These containers will then be fastened securely by means of screws to a connecting plate which connection can be effected both on Earth as well as in orbit. These connecting plates in turn are fastened to the space vehicle structure. The payload is brought into operation through electrical communication and thermo-technical connections as well as as far as supply and disposal is concerned.
This particular arrangement requires mechanical fastening on the container fastening plate by an astronaut which requires him to exercise a great deal of skill. This by and in itself is not a drawback since astronauts are highly skilled people in the first place. However, in the case of large containers accommodating a large payload and being characterized by a large mass, an accurate alignment of the connecting and fastening structure poses some difficulty in spite of conical guide elements providing indexing and centering function. Moreover, some connections are provided outside of the confines of the particular container which on the basis of a fairly large distances from the payload itself require installation of relatively long connecting cables, conduits or the like. Cable and conduits by themselves amount to additional weight one may wish to avoid since any structural weight that is needed just for conduction purposes and reduces the available payload capacity. Another drawback of this device is that the particular payload transport and operating structure is limited to a fixed number of basic surface areas. Payloads that happen to be larger from an overall point of view than the largest container base will therefore have to be accommodated by a second container and this particular payload must be distributed over two containers.